package com.javaee.websocket;
import java.io.IOException;
import java.util.ArrayList;

import org.apache.log4j.Logger;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketSession;
import org.springframework.web.socket.handler.TextWebSocketHandler;

public class SpringWebSocketHandler extends TextWebSocketHandler{
	
	 private static final ArrayList<WebSocketSession> users;//这个会出现性能问题，最好用Map来存储，key用userid
	    private static Logger logger = Logger.getLogger(SpringWebSocketHandler.class);
	    static {
	        users = new ArrayList<WebSocketSession>();
	    }
	    
	    public SpringWebSocketHandler() {
	        // TODO Auto-generated constructor stub
	    }

	    /**
	     * 连接成功时候，会触发页面上onopen方法
	     */
	    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
	        // TODO Auto-generated method stub
	        System.out.println("connect to the websocket success......当前数量:"+users.size());
	        users.add(session);
	        //这块会实现自己业务，比如，当用户登录后，会把离线消息推送给用户
	        //TextMessage returnMessage = new TextMessage("你将收到的离线");
	        //session.sendMessage(returnMessage);
	    }
	    
	    /**
	     * 关闭连接时触发
	     */
	    public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception {
	        logger.debug("websocket connection closed......");
	        String username= (String) session.getAttributes().get("WEBSOCKET_USERNAME");
	        System.out.println("用户"+username+"已退出！");
	        users.remove(session);
	        System.out.println("剩余在线用户"+users.size());
	    }

	    /**
	     * js调用websocket.send时候，会调用该方法
	     */
	    @Override    
	    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
	        super.handleTextMessage(session, message);
	    }

	    public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
	        if(session.isOpen()){session.close();}
	        logger.debug("websocket connection closed......");
	        users.remove(session);
	    }

	    public boolean supportsPartialMessages() {
	        return false;
	    }
	    
	    
	    /**
	     * 给某个用户发送消息
	     *
	     * @param userName
	     * @param message
	     */
	    public void sendMessageToUser(String userName, TextMessage message) {
	        for (WebSocketSession user : users) {
	            if (user.getAttributes().get("WEBSOCKET_USERNAME").equals(userName)) {
	                try {
	                    if (user.isOpen()) {
	                        user.sendMessage(message);
	                    }
	                } catch (IOException e) {
	                    e.printStackTrace();
	                }
	                break;
	            }
	        }
	    }
	    
	    /**
	     * 给所有在线用户发送消息
	     *
	     * @param message
	     */
	    public void sendMessageToUsers(TextMessage message) {
	        for (WebSocketSession user : users) {
	            try {
	                if (user.isOpen()) {
	                    user.sendMessage(message);
	                }
	            } catch (IOException e) {
	                e.printStackTrace();
	            }
	        }
	    }
	
}
